/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

package org.apache.flink.test.example.java;

import org.apache.flink.examples.java.graph.PageRank;
import org.apache.flink.test.testdata.PageRankData;
import org.apache.flink.test.util.MultipleProgramsTestBase;
import org.apache.flink.util.FileUtils;

import org.junit.After;
import org.junit.Before;
import org.junit.Rule;
import org.junit.Test;
import org.junit.rules.TemporaryFolder;
import org.junit.runner.RunWith;
import org.junit.runners.Parameterized;

import java.io.File;
import java.util.UUID;

/**
 * Test for {@link PageRank}.
 */
@RunWith(Parameterized.class)
public class PageRankITCase extends MultipleProgramsTestBase {

	public PageRankITCase(TestExecutionMode mode){
		super(mode);
	}

	private String verticesPath;
	private String edgesPath;
	private String resultPath;
	private String expected;

	@Rule
	public TemporaryFolder tempFolder = new TemporaryFolder();

	@Before
	public void before() throws Exception{
		final File folder = tempFolder.newFolder();
		final File resultFile = new File(folder, UUID.randomUUID().toString());
		resultPath = resultFile.toURI().toString();

		File verticesFile = tempFolder.newFile();
		FileUtils.writeFileUtf8(verticesFile, PageRankData.VERTICES);

		File edgesFile = tempFolder.newFile();
		FileUtils.writeFileUtf8(edgesFile, PageRankData.EDGES);

		verticesPath = verticesFile.toURI().toString();
		edgesPath = edgesFile.toURI().toString();
	}

	@After
	public void after() throws Exception{
		compareKeyValuePairsWithDelta(expected, resultPath, " ", 0.01);
	}

	@Test
	public void testPageRankSmallNumberOfIterations() throws Exception {
		PageRank.main(new String[]{
				"--pages", verticesPath,
				"--links", edgesPath,
				"--output", resultPath,
				"--numPages", PageRankData.NUM_VERTICES + "",
				"--iterations", "3"});
		expected =  PageRankData.RANKS_AFTER_3_ITERATIONS;
	}

	@Test
	public void testPageRankWithConvergenceCriterion() throws Exception {
		PageRank.main(new String[]{
				"--pages", verticesPath,
				"--links", edgesPath,
				"--output", resultPath,
				"--numPages", PageRankData.NUM_VERTICES + "",
				"--vertices", "1000"});
		expected = PageRankData.RANKS_AFTER_EPSILON_0_0001_CONVERGENCE;
	}
}
